Conventionally, when measuring, from the outside, something to be measured that is within a space wherein, for example, a toxic gas is produced, a through hole is provided, for the measurement, in a wall that surrounds the space, and an electronic device for measuring is attached in the through hole. In this case, the attaching part of the electronic device uses a sealing structure that cuts off between the space and the outside air. As a conventional sealing structure of this type there is, for example, that which is disclosed in Japanese Unexamined Patent Application Publication 2004-11895 (“JP '895”).
The sealing structure disclosed in JP '895 seals between a cylindrical member that structures a portion of a through hole, and a flame sensor that is housed within the cylindrical member. The space between the cylindrical member and the main body of the sensor is sealed by a sealing material.
In this flame sensor, the use of a sealing structure at the electrode terminal side as well makes it possible to achieve a further improvement in the sealing performance. When sealing the electrode terminal side of the flame sensor, a liquid or gel potting agent or adhesive agent is often used to fill around the electrode terminals.
However, this seal performed by filling with a liquid or gel potting agent or adhesive agent has poor productivity, and bubbles may occur therein, reducing the airtightness, and thus there has been the danger that the desired sealing performance may not be produced. The reason why productivity has been poor is that the potting agent or adhesive agent requires some time to harden, and thus it has been necessary to wait, after filling, before transferring to the next step.
The reason why bubbles have been produced is that sometimes the filling is performed while incorporating the surrounding air into the filling agents. In order to prevent this, it is necessary to perform degassing by applying a vacuum, increasing the manufacturing cost.
The reason why the airtightness is low is that, after filling, the adhesive part of the filling agent peels off, due to fluctuations in temperature.
The present invention is to solve problems such as set forth above, and the object thereof is to provide an electronic device holding socket that can seal, with higher productivity and reliability, the electrode side of an electronic device, and to provide a flame sensor with improved productivity and sealing performance.